As a fitness professional, it's always difficult to go into a gym and watch others exercise. Why? Because there is mistake after mistake being committed everywhere I look—some potentially dangerous, others, well, useless. I am not alone in my observations, either. I went to some of the top trainers in North America to see what they felt were some of the most frequently performed workout blunders, and here's what they had to say.

Absolutely Abominable Abs

No doubt about it—abdominal work won as being the exercise most often performed incorrectly. In my opinion, though, some of the blame for this lies with the fitness industry. In group fitness classes, instructors lead participants in an infinite number of crunches, or as Tony Golden, ACE-certified lead personal trainer for BodyPotential.com calls it, "750 ballistic crunches a minute, with a complete lack of form or any idea of what they are doing."

The first thing to pay attention to with ab work is form. "The solution is to slowly squeeze the abdominal muscles, while keeping [the low back] in contact with the floor or mat," instructs Golden. "I tell people to imagine they have a grapefruit between their chin and their chest, and that the goal is to lift their shoulders off the floor, maintain eye contact with the ceiling at all times, and keep their abdominal muscles tightened during both the lifting and lowering stages of the crunch."

"Work at a slow speed, and position the elbows parallel to the ears," adds Amanda Vogel, MA, fitness presenter and the executive director of group exercise at FitCity for Women in Vancouver, British Columbia. "You'll be less likely to pull on the head and neck." Placing the hands just behind the ears, rather than lacing the fingers together helps, too.

Susan Cantwell, Nike Fitness Athlete and author of Mind Over Matter , recommends that once you're able to perform 15-25 correct crunches with ease, then you can add weight, declines, and stability balls (not necessarily all at once, though!). "My recommendations? Lower the amount of mind numbing reps you perform, and increase the difficulty of each individual repetition," advises Cantwell.

The Funky Chicken

"It amazes me how people somehow manage to do three sets of biceps curls in ten seconds," says Golden. "Their arms look like pistons flying through each repetition faster than a humming bird flaps its wings!" Part of the problem with this is that you don't move through a full range of motion, and therefore, are not working the muscle to it's peak.

Another problem is that when you move the weights, or even just your limbs, this quickly, "you're using too much momentum and not enough muscle," explains Cantwell.

"My advice for these folks? Slow down!" exclaims Golden. "During the lifting portion of the exercise, lift the weight in a two count, and then lower it in a four count. Exhale while lifting; inhale as you lower the weight."

The Hercules Syndrome

Attempting to lift too much weight is a common mistake, especially among men—and one that is potentially quite dangerous. Three things happen:

  • You have a tendency to jerk the weight up, placing a tremendous amount of strain on the joints.
  • You don't move through a full range of motion.
  • You're using momentum, not muscle.

Combine these errors together, and you've got a recipe for injury. Lastly, when you've got the weight stack maxed out beyond what you can handle, the weights crash down between each rep, and this is just annoying!

If you don't know your maximum weight, ask a trainer to help you determine it.

The Big Y (for Yawn, That Is)

"This one is so common, that I consider it one of the main reasons that people drop out [of their fitness programs]," says Cantwell. "When people do not see results from their efforts, they begin to lose interest, and the boredom factor comes into play. In order to progress and avoid boredom and burnout, exercisers should change their programs every six to eight weeks."

How can you mix up it up? "If you have been doing the same cardio program for months, try intensifying your workouts by adding interval training," says Vogel. "And take a look at your resistance training exercises. Do you always gravitate to the same machines or exercises?" Vogel suggests making an appointment with a qualified personal trainer every so often, to have him or her evaluate your program and show you alternatives to your usual routine.

The Herky-Jerky

According to Brian Cowen, owner of Personal Trainer at Home in the Washington, DC area, there are two main mistakes people make when it comes to stretching: not warming up first, and stretching quickly and erratically.

He advises not using stretching as the warm-up. "The best warm-up for a run [or other aerobic activity] is to start off slow, then pick up your speed. Prior to lifting weights, you should warm-up with 15-20 minutes of light cardio. Save your stretching for after the run or workout when your muscles are warm and pliable." Most experts agree, for the average exerciser, static stretching is best. "Stretch slowly," says Cowen, "and hold at the point of slight discomfort for at least 15-20 seconds." No bouncing allowed!

Spot Not!

Saddle bags, love handles, the old flapping wing under your arm… Think that by moving that specific trouble area you will magically make it disappear? Think again!

"Too often I've witnessed, especially women, still trying to spot reduce. They seem to neglect the body as a whole when they train, and want to set up programs designed to work specific areas only," says Amy Bomar, owner and founder of Fitlaunch.com.

Vogel recommends focusing on a total body conditioning program: cardio to burn fat, resistance training for all major muscle groups. "I really encourage people to avoid seeing body parts as 'problem areas,'" explains Vogel. "Instead, use fitness as a way to focus on the way your body moves and functions as a whole. Enjoy the experience of being fit!"

Learn the Proper Techniques

Take the time to learn correct exercise form and function before you hit the gym. Read fitness magazines, books, and web sites. Set up an appointment with a personal trainer. Many clubs offer or even require new fitness members to receive instruction on the equipment before setting off on their own. Use this time to ask questions and really try out the equipment. Take notes and schedule a second, third, or fourth appointment if you have to. Before you know it, you'll be an old pro.